Few clinical issues create more anxiety for parents than an enlarged cervical lymph node. They need to know that it is not cancer and they need to know today. The experienced pediatric surgeon usually has a good feel for whether an enlarged lymph node is something to be concerned about or can be safely observed and the parents reassured. Unfortunately the only option for sampling a lymph node in a child is a surgical procedure under general anesthesia, which is generally safe and usually straightforward, but entails a certain amount of risk and an obligatory scar. This means that the surgeon should have a high index of suspicion before recommending a biopsy. Fortunately, a period of observation is almost always safe, even in the case of a malignant process, so, when in doubt, a brief delay can help one to make the best recommendation.
In children, FNA is simply not a good option for the evaluation of cervical masses: pediatric pathologists have little experience with the technique, most children will not let you come near them with a needle, and, most importantly, the most common neoplastic processes seen in children (lymphoma and leukemia) cannot be reliably differentiated from an inflammatory process by FNA. Likewise, a neoplastic process cannot be excluded on the basis of blood tests, serologies, or medical imaging. What we are left with then is the history, the physical examination, and the growth pattern of the node. A lymph node that is larger than 1.5 cm and continues to grow over time, especially if it is located in an unusual location (supraclavicular), should be excised. Likewise, the patient with constitutional symptoms (the presence or absence of which should be specifically documented at the initial visit) should undergo biopsy.
A typical busy pediatric surgeon will see at least one or two children with an enlarged lymph node every week. Most can be simply observed with no further studies, but nearly all should be encouraged to return for at least one follow-up visit in 2–3 weeks. At the other extreme is the rare patient with systemic symptoms and a worrisome node that clearly needs to be excised for biopsy. These patients should be scheduled for surgery and at minimum have a CBC with differential and a chest X-ray to rule out a mediastinal mass. The remainder will have clearly pathologic lymphadenopathy but no clear indication that a neoplastic process is necessarily involved. These patients should be scheduled for follow up in no more than 2–3 weeks and should undergo a work up: CBC w/diff.; serologies for cat scratch, toxoplasmosis, and mononucleosis, depending on what is endemic in the area; and a chest X-ray. If there are risk factors, a PPD might be prudent. In some cases in which a bacterial lymphadenitis is suspected, an empiric 7-day trial of antibiotics is reasonable, albeit controversial. A node involved with tumor almost never get smaller without treatment, so a node that shrinks can probably be observed. However, lymphoma can regress rapidly when the patient is given corticosteroids (for example for a coincidental asthma flare), in which case a biopsy becomes imperative.
Cervical lymph node biopsy is a delicate procedure not to be taken lightly. There is always the risk of nerve injury and attention should be paid to scar placement for cosmesis and comfort. A small transverse incision placed in a skin crease is preferred. Once the platysma has been breached, the remainder of the dissection should be by careful blunt dissection only. A curved hemostat should be used to gently push adjacent tissues away from the capsule of the lymph node and nothing should be cut or cauterized. With proper technique, the node will gently rise up to meet the incision and the vessels at the hilum can be ligated or cauterized with precision right at the capsule. The goal should be complete excision of the node, but this can be done in piece-meal fashion. Lymph nodes that surprise the surgeon by being excessively vascular can be assumed to represent metastatic thyroid carcinoma (or another even less common neoplasm). The incision should be closed only at the level of the platysma and the skin as deeper sutures are not necessary and increase the risk of nerve injury. Finally, the child with an enlarged lymph node that is highly suspicious for malignancy should be evaluated by a pediatric oncologist before surgery so that a proper work up can be initiated, including a bone marrow biopsy to be performed while the patient is under general anesthesia.